To calculate a down payment for a mortgage in the United States, determine the loan type and required percentage. Conventional loans typically mandate a 20% down payment, while FHA loans require 3.5% for most buyers, VA loans offer 0% down for qualified veterans, and USDA loans need 0-6% depending on income. Subtract the down payment percentage from the home purchase price to find the loan amount. For example, a $300,000 home with a 20% down payment requires a $60,000 payment, leaving a $240,000 mortgage. Lenders may also consider debt-to-income ratios and credit scores when finalizing terms.

The down payment percentage impacts mortgage affordability, interest rates, and additional costs. A 20% down payment eliminates private mortgage insurance (PMI), reducing monthly expenses. Lower down payments increase loan amounts, raising interest rates and monthly payments. According to Fannie Mae, 20% down payments are standard for conforming loans, ensuring lower risk for lenders. FHA loans, backed by the U.S. Department of Housing and Urban Development, permit 3.5% down for borrowers with credit scores above 580, catering to lower-income buyers. VA loans, for military veterans, require no down payment but mandate a funding fee, typically 2.15-3.6% of the loan amount. USDA loans, for rural areas, require 0% down but cap household incomes at 115% of median area levels. Data from the Urban Institute (2022) shows that buyers with 20% down payments save an average of $100 monthly compared to those with 5% down due to PMI and lower rates. Additionally, the Federal Reserve reports that 30% of first-time buyers in 2023 used down payment assistance programs, highlighting the role of external support in reducing barriers. Ultimately, the down payment strategy balances upfront costs, long-term affordability, and eligibility for government-backed programs.